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Abstract

The current knowledge of flow parameters for terrestrial two-phase flow was
developed through experiments that collected hundreds to thousands of data points.
However, the cost associated with microgravity testing make collecting such amounts of
microgravity two-phase flow data difficult. Multiple researchers have postulated the
microgravity drift flux model parameters to predict void fraction, however, these
methods were initially developed with no consideration given to a microgravity
environment. The purpose of this thesis was to develop a process by which results from
multiple microgravity experiments can be compared on a similar medium and used to
develop a larger viable data set than what was previously available and to reliably
calculate a value for the void fraction from the available data.
Development of multiphase systems for microgravity requires accurate
prediction methods. Utilizing data from multiple microgravity two-phase flow
experiments, a statistically consistent slug flow database has been created. The data from
13 different microgravity two-phase flow experiments was vetted using a combination of
parametric and non-parametric statistical tests to develop a valid model for the drift flux
parameters that meet the axioms of a linear model. The result was a statistically
consistent microgravity slug flow data base consisting of 220 data points from 8
different experiments and the associated values for the concentration parameter, Co, and
drift velocity, u_(gj). A key component for this model was redefining the assumptions in
the drift flux model to accurately represent microgravity conditions in calculating the
drift flux parameters. The resultant drift flux parameters are a distribution parameter, Co
= 1.336 ± 0.013 and a drift velocity, u_(gj) = -0.126 ± 0.020.